What is the Binaural Listening mode in the 360 All-Around program?

Question

Answer

The Binaural Listening mode is one of three microphone modes embedded in the 360 All-Around program. This program is the default in premium level ReSound hearing aids Resound OMNIA, ReSound Nexia and ReSound Vivia. The Binaural Listening mode is activated automatically when both speech and moderately loud noise are detected in the user’s environment and the 360 All-Around program is in use.

The Binaural Listening mode is based on the observation that listeners can take advantage of the location of the ears on each side of the head to either enhance or sup­press sounds in the environments at will. When the en­vironment is moderately complex, listeners shift away from relying primarily on spatial cues, relying instead on the ear that has the best representation of the desired sound. In other words, the “better ear” for the sound. The directivity patterns of both ears contribute to this ability to focus and the SNR at the better ear predominates.¹ This idea has been extended to hearing aid directional microphones and found to hold true. When fit with a di­rectional microphone on one side and an omnidirectional microphone on the other, listeners perform equally well as when fit with directional microphones on both ears in the conventional speech-in-noise test setup.^2,3 The Binaural Listen­ing mode optimizes spatial directivity patterns on the two ears to ensure there is always a “better ear” for whatever the hearing aid wearer wants to hear regardless of where that sound is in the environment.

When the Binaural Listening mode is activated, one ear will receive the signal from a four-microphone binaural beamformer, providing a strong directionality to the front between 500Hz and 5kHz. The other ear will receive a signal with an optimized omnidirectional response, maintaining audibility of surrounding sounds even between 500Hz and 5kHz (where sounds are being reduced by the four-microphone beamformer on the other ear). The combination of these directivity patterns provides greater contrast in the inputs to the two ears, giving the user improved opportu­nities to rely on better ear listening and spatial unmasking.

References

1. Zurek PM. Binaural advantages and directional effects in speech intelligibility. In G. Studebaker & I. Hochberg (Eds.), Acoustical Factors Affecting Hearing Aid Performance. Boston: College-Hill, 1993.

2. Cord MT, Walden BE, Surr RK, Dittberner AB. Field evaluation of an asymmetric directional microphone fitting. J Am Acad Audiol. 2007;18:245-56.

3. Bentler RA, Egge JLM, Tubbs JL, Dittberner AB, Flamme GA. Quantification of directional benefit across different polar response patterns. J Am Acad Audiol. 2004:15;649-59.